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to the question of placement (location and size). The feasibility
options recommendod in this section, along with an understanding of
historic habitat losses and desired neodo, should form the basis for
development of a bay-wide restoration and/or enhancement program for
Tanpa Bay.
Identification of Potential Mitigation Sites
Twelve potential mitigation sites wore evaluated: six in
Hillsborough Bay, flvo in Old Tampa Bay, and one in Lower Tampa Bay.
The proposed mitigation plans for tho Hillsborough Bay sites would
involve filling 47 ha of old dredged borrow pits, filling 165.1 ha of
oubtidal sand flats for creation of mangrove or marsh habitat, and
scraping down 52.2 ha of disturbed upland and transitional wetlands
habitat for marsh creation. The proposed mitigation plans for the
Old Tampa Bay sites would Involve filling 132 ha of dredged borrow
pits and scraping down 121 ha of disturbed upland. At the Lower
Tampa Bay site, the plan calls for scraping down of 2.5 ha of
disturbed upland for marsh creation. After evaluating the value of
existing benthic habitats, filling subtldal areas may not be
acceptable as mitigation. Additional projects for Manatee County are
being developed by the FDNR (Evans, 1985).
At a majority of tho sites evaluated or selected as suitable for
habitat creation, submerged lands are owned by the TPA or other State
or local public agencies (e.g., SWFWMD). Of the 12 sites proposed,
11 are located all or in part on submerged lands owned by tho TPA or
other governmental entitles. Three sites encompass some privately
owned land. Prioritization of the .sites should be based on data
concerning wetland habitat loss (i.e., Tampa Bay Trend Analysis
Study) for each area of the bay and/or needs tor particular habitats
or species. The wetland trend study has not been completed and
identification of needs for particular habitats or species has not as
yet been attempted. Criteria that could be used to assign site
priority In the absence of information on habitat loss and needs
include: (1) land ownership (use of public owned lands will minimize
coats)) (2) needs for and feasibility ot restoration in relation to
future port-related projects) and (3) relationships to bay-wide
restoration efforts and habitat needs. Site selection should also
involve consideration of anticipated TPA needs in terms of expansion,
improvement, or maintenance, and the types and amounts of unavoidable
habitat losses projected. If the goal is to mitigate unavoidable
losses due to future port development, a balance between habitat
needs and anticipated unavoidable losses should be established.
Additional important factors to be considered in relation to
site selection include pumping distances, suitability of dredged
material for habitat creation, and the quantity of dredged material
needed. Only sites within Hillsborough County may prove feasible
from an engineering viewpoint) sites in Old Tampa Bay, excluding